A person reading your sentence would not be doing the operations in the correct order, but in their order in your sentence.

J: J: "One plus two times three minus four". The person will do the addition first, based on your sentence, if it's standing alone.

If this is true, then the brackets, parenthesis or whatever you care to call them in "(1+2)x3" would make no difference, and you would say that "one plus two times three" and "open bracket one plus two close bracket times three" both equal nine.

Of course, there are many people who would say that the first one equals nine; however their failure to understand the correct order of mathematical operations would get them unstuck as soon as you reach "times seven" in the original question:

(1+2)×3-4+(5+6)×7+8+9

The question that I was answering was how to accurately convey a written mathematical expression to another person (who understands the order of mathematical operations) by means of spoken words (via a phone call, for instance). I do not expect the person I am speaking to to do each calculation is it is spoken, but to either:

write it down

remember it all and work it out at the end

keep a running total, but not incorporate any additions or subtractions until the next operation is known (but this gets complicated if powers are involved).

I don't see any need to consider people who don't know the order of operations, because they would not have arrived at 99 in the OP's calculation in the first place.